Summary: We investigated potential indicators of climate change effects on key wildlife and ecosystem resources in coastal Long Island Sound (LIS). Our focus was on biological indicators with high potential to show climate responses, available historical data, ease of cost-effective future data collection, and the ability to inform real-world management decisions. For wildlife measures with long enough time series, we investigated whether variation was explained by a set of core parameters: measures of temperature, precipitation, and sea level. We found that beach-nesting and colonial waterbirds, which represent some of the longest time series for wildlife in LIS, are not strongly influenced by the core parameters. In contrast, several saltmarsh bird and plant measures are strong indicators of sea level and tidal flooding. Additionally, we conducted pilot investigations and collected baseline data for other potential indicators in an attempt to address topics that lacked a historical record, in particular rates of ecosystem change in areas thought to be experiencing marine transgression. Overall, our results suggest that (1) several components of saltmarsh ecosystems are already being affected by increased coastal flooding and (2) coastal forest ecosystems are potentially resilient to change in the face of increased coastal flooding. This temporal mismatch in responses to coastal flooding will likely create challenges for management aimed at saltmarsh conservation in LIS. Additional research and monitoring is needed to understand rates of marine transgression and the factors influencing them.

A broad array of Sentinel characteristics of the Long Island Sound ecosystem have been identified by the Sentinel Monitoring Work Group. These have been linked to physical and chemical driver variables that are characteristic of the environment. We propose to quantify local changes in the environment through analysis of changes in the driver variables and assess whether they are a consequences of global scale climate change. This will assist future analysis of ecosystem responses and guide management priorities on mitigation and adaptation strategies. Our approach is to establish long time-series of measurements of driver variables and aggregate them into a regional climatology. We will use objective and repeatable statistical procedures to merge data from different sources. We will make the raw data, the climatologies, and the processing software available through the project website. We will then analyze the merged series to detect long term trends and cycles, and compare the results with available continent and global scale analyses. We will also make preliminary assessments to changes in characteristics of lobster and marsh habitats and coastal erosion rates. The results will be disseminated to the bistate Sentinel Monitoring Work Group through a meeting/webinar and a report, and to the broader community through the project website and a scientific journal article.

A summary of the report can be found at this link and the data used in the report are available at this link.

The purpose of the research proposed here is to determine if accretion rates in LIS salt marshes are keeping pace with sea level rise. Additionally, we will put these new measurements into a larger historical and environmental context by synthesizing existing data. Data from this research will then be made available so that LIS stakeholders may examine it and use it as needed. The specific objectives of this proposal are to:

Quantify salt marsh accretion rates and other site characteristics at a select set of sites in Long Island Sound using two dating methods (137Cs and ‘excess’ 210Pb).

Collect and synthesize data throughout LIS for environmental factors indicative of local human impacts and climate change including: nutrient loading, air and water temperatures, sea level rise, wind, and precipitation; additionally we will gather all previously measured salt marsh accretion rates in LIS for comparisons to the data we collect here in this study.

This project is an application of the SLAMM model to coastal Connecticut and New York to assess tidal marsh vegetation change and locations of marsh transgression. SLAMM is an acronym for Sea Level Affecting Marshes Model. Final reports are currently available for Connecticut and Westchester County including various maps and GIS coverages.